This invention relates to a device for injecting gas into liquids, and more particularly, relates to a method and apparatus for carbonating or maintaining the carbonation of bottled beverages.
Carbonated beverages, such as sodas, sparkling water, beer, etc., are typically stored in a bottled container. The most common of these are one or two liter P.E.T. bottles made from plastic. The P.E.T. bottles have a screw-on cap that can be removed and replaced during use. However, if the cap is taken off the bottle, the carbonated beverage in the bottle will begin to lose its CO.sub.2, carbonation or fizz.
In addition, as the beverage is consumed and removed from the bottle, a greater amount of air remains in the bottle in proportion to the amount of fluid in the bottle. Consequently, the gas in the liquid dissipates into the air in the bottle, even with the cap on the bottle, resulting in loss of carbonation.
Many prior devices have tried to slow the loss of carbonation in the liquid by increasing the air pressure in the bottle. However, because air is still in the bottle, carbonation is eventually lost.
Another drawback to having air in the bottled container is that for certain natural carbonated beverages, such as fruit juices and beer, air can cause these beverages to spoil, stale or degrade. Further, when air is present in the container, the beverage may be prevented from being re-carbonated.
When carbonating beverages, it is desirable to leave the cap on the container once CO.sub.2 gas is fed into the container without permitting air to contaminate the beverage. It is then desirable to shake and refrigerate the beverage to dissolve all the CO.sub.2 gas.
Many prior art devices do not permit easy injection of CO.sub.2 gas into a bottle with subsequent easy removal of the injection device.